1 files changed, 23 insertions, 91 deletions

diff --git a/net/netfilter/nf_conntrack_extend.c b/net/netfilter/nf_conntrack_extend.c
index 008299b7f78f..6c605e88ebae 100644
--- a/net/netfilter/nf_conntrack_extend.c
+++ b/net/netfilter/nf_conntrack_extend.c
@@ -18,17 +18,14 @@
 
 static struct nf_ct_ext_type __rcu *nf_ct_ext_types[NF_CT_EXT_NUM];
 static DEFINE_MUTEX(nf_ct_ext_type_mutex);
+#define NF_CT_EXT_PREALLOC	128u /* conntrack events are on by default */
 
-void __nf_ct_ext_destroy(struct nf_conn *ct)
+void nf_ct_ext_destroy(struct nf_conn *ct)
 {
 	unsigned int i;
 	struct nf_ct_ext_type *t;
-	struct nf_ct_ext *ext = ct->ext;
 
 	for (i = 0; i < NF_CT_EXT_NUM; i++) {
-		if (!__nf_ct_ext_exist(ext, i))
-			continue;
-
 		rcu_read_lock();
 		t = rcu_dereference(nf_ct_ext_types[i]);
 
@@ -41,54 +38,26 @@ void __nf_ct_ext_destroy(struct nf_conn *ct)
 		rcu_read_unlock();
 	}
 }
-EXPORT_SYMBOL(__nf_ct_ext_destroy);
-
-static void *
-nf_ct_ext_create(struct nf_ct_ext **ext, enum nf_ct_ext_id id,
-		 size_t var_alloc_len, gfp_t gfp)
-{
-	unsigned int off, len;
-	struct nf_ct_ext_type *t;
-	size_t alloc_size;
-
-	rcu_read_lock();
-	t = rcu_dereference(nf_ct_ext_types[id]);
-	if (!t) {
-		rcu_read_unlock();
-		return NULL;
-	}
-
-	off = ALIGN(sizeof(struct nf_ct_ext), t->align);
-	len = off + t->len + var_alloc_len;
-	alloc_size = t->alloc_size + var_alloc_len;
-	rcu_read_unlock();
-
-	*ext = kzalloc(alloc_size, gfp);
-	if (!*ext)
-		return NULL;
-
-	(*ext)->offset[id] = off;
-	(*ext)->len = len;
-
-	return (void *)(*ext) + off;
-}
+EXPORT_SYMBOL(nf_ct_ext_destroy);
 
-void *__nf_ct_ext_add_length(struct nf_conn *ct, enum nf_ct_ext_id id,
-			     size_t var_alloc_len, gfp_t gfp)
+void *nf_ct_ext_add(struct nf_conn *ct, enum nf_ct_ext_id id, gfp_t gfp)
 {
+	unsigned int newlen, newoff, oldlen, alloc;
 	struct nf_ct_ext *old, *new;
-	int newlen, newoff;
 	struct nf_ct_ext_type *t;
 
 	/* Conntrack must not be confirmed to avoid races on reallocation. */
 	NF_CT_ASSERT(!nf_ct_is_confirmed(ct));
 
 	old = ct->ext;
-	if (!old)
-		return nf_ct_ext_create(&ct->ext, id, var_alloc_len, gfp);
 
-	if (__nf_ct_ext_exist(old, id))
-		return NULL;
+	if (old) {
+		if (__nf_ct_ext_exist(old, id))
+			return NULL;
+		oldlen = old->len;
+	} else {
+		oldlen = sizeof(*new);
+	}
 
 	rcu_read_lock();
 	t = rcu_dereference(nf_ct_ext_types[id]);
@@ -97,15 +66,19 @@ void *__nf_ct_ext_add_length(struct nf_conn *ct, enum nf_ct_ext_id id,
 		return NULL;
 	}
 
-	newoff = ALIGN(old->len, t->align);
-	newlen = newoff + t->len + var_alloc_len;
+	newoff = ALIGN(oldlen, t->align);
+	newlen = newoff + t->len;
 	rcu_read_unlock();
 
-	new = __krealloc(old, newlen, gfp);
+	alloc = max(newlen, NF_CT_EXT_PREALLOC);
+	new = __krealloc(old, alloc, gfp);
 	if (!new)
 		return NULL;
 
-	if (new != old) {
+	if (!old) {
+		memset(new->offset, 0, sizeof(new->offset));
+		ct->ext = new;
+	} else if (new != old) {
 		kfree_rcu(old, rcu);
 		rcu_assign_pointer(ct->ext, new);
 	}
@@ -115,45 +88,10 @@ void *__nf_ct_ext_add_length(struct nf_conn *ct, enum nf_ct_ext_id id,
 	memset((void *)new + newoff, 0, newlen - newoff);
 	return (void *)new + newoff;
 }
-EXPORT_SYMBOL(__nf_ct_ext_add_length);
-
-static void update_alloc_size(struct nf_ct_ext_type *type)
-{
-	int i, j;
-	struct nf_ct_ext_type *t1, *t2;
-	enum nf_ct_ext_id min = 0, max = NF_CT_EXT_NUM - 1;
-
-	/* unnecessary to update all types */
-	if ((type->flags & NF_CT_EXT_F_PREALLOC) == 0) {
-		min = type->id;
-		max = type->id;
-	}
-
-	/* This assumes that extended areas in conntrack for the types
-	   whose NF_CT_EXT_F_PREALLOC bit set are allocated in order */
-	for (i = min; i <= max; i++) {
-		t1 = rcu_dereference_protected(nf_ct_ext_types[i],
-				lockdep_is_held(&nf_ct_ext_type_mutex));
-		if (!t1)
-			continue;
-
-		t1->alloc_size = ALIGN(sizeof(struct nf_ct_ext), t1->align) +
-				 t1->len;
-		for (j = 0; j < NF_CT_EXT_NUM; j++) {
-			t2 = rcu_dereference_protected(nf_ct_ext_types[j],
-				lockdep_is_held(&nf_ct_ext_type_mutex));
-			if (t2 == NULL || t2 == t1 ||
-			    (t2->flags & NF_CT_EXT_F_PREALLOC) == 0)
-				continue;
-
-			t1->alloc_size = ALIGN(t1->alloc_size, t2->align)
-					 + t2->len;
-		}
-	}
-}
+EXPORT_SYMBOL(nf_ct_ext_add);
 
 /* This MUST be called in process context. */
-int nf_ct_extend_register(struct nf_ct_ext_type *type)
+int nf_ct_extend_register(const struct nf_ct_ext_type *type)
 {
 	int ret = 0;
 
@@ -163,12 +101,7 @@ int nf_ct_extend_register(struct nf_ct_ext_type *type)
 		goto out;
 	}
 
-	/* This ensures that nf_ct_ext_create() can allocate enough area
-	   before updating alloc_size */
-	type->alloc_size = ALIGN(sizeof(struct nf_ct_ext), type->align)
-			   + type->len;
 	rcu_assign_pointer(nf_ct_ext_types[type->id], type);
-	update_alloc_size(type);
 out:
 	mutex_unlock(&nf_ct_ext_type_mutex);
 	return ret;
@@ -176,11 +109,10 @@ out:
 EXPORT_SYMBOL_GPL(nf_ct_extend_register);
 
 /* This MUST be called in process context. */
-void nf_ct_extend_unregister(struct nf_ct_ext_type *type)
+void nf_ct_extend_unregister(const struct nf_ct_ext_type *type)
 {
 	mutex_lock(&nf_ct_ext_type_mutex);
 	RCU_INIT_POINTER(nf_ct_ext_types[type->id], NULL);
-	update_alloc_size(type);
 	mutex_unlock(&nf_ct_ext_type_mutex);
 	synchronize_rcu();
 }